Process for making insulating material.



TEN

FICE.

WILLIAM R. SEIGLE, OF NASHUA, NEW HAMPSHIRE.

rnocnss son MAKING msonarme MATERIAL.

No Drawing.

Specification of Letters Patent. Patented May 31, 1910. Application filed December 20, 1909. Serial No. 534,045.

To all whom it may concern:

Be it known that I, WILLIAM R. Serene, acitizen of the United States, and resident of Nashua, in the county of Hillsboro and State of New Hampshire, have invented new and useful Improvements in Processes for with magnesium hydrate, with a liquid hydroc'arbon, preferably a hydrocarbon which is solid at ordinary temperatures, and which in order to be made to saturate the porous refractory material, is raised to-a high temperature. Insulating materials made according to the said process are of high insuating property and dielectric strength and have the advantage also of being substantially homogeneous in structure and free from seams or faults. Especially is this true when the refractory material subjected to the saturation process has previously been made by such rocesslas is described in Letters Patent of the United States No. 847,293 granted to Charles I]. Norton March 12, 1907, whereby heavy pressure is employed in theformation of the sheet, slab or other article composed of the said refractory material. Even though such refractory material be repared for saturation withliquid hydrocar on by having the air exhausted as ar as possible or practicable from its pores, and by being heated, it requires considerable time for the liquid hydrocarbon to penetrate thoroughly to all parts of the body being saturated, and this time, of course, increases,

with the bulk of the body under treatment.

My invention whichis the subject of this specification, consists in an improvement by which substantially the same class of insulating material, as that above described, may be produced but with far greater celerity and therefore economy.

Taking, for example, the fiber concrete described in PatentNo. 847,293, which is composed of asbestiform fiber mixed with magnesium oxid and water, and then subjected to heavy pressure accompanied by expression of surplus water while the ma nesium oxid is undergoing hydration, I a d to the original mixture of fiber andv cementitious material a quantity'of finely divided liquefiable solid hydrocarbon; for instance, the harder pitches'or asphalts; in fact, any liquefiable hydrocarbon which is substantially solid at ordinary temperatures to admit of its being... comminuted and effectively 1 distributed through the mass of fiber whic is one of the chief ingredients of the composition. I then proceed as before and as described in the said Patent No. 847 93, or I may carry out the process accor in to such modifications and improvements 0 the process described in the last aforesaid patent as are set forth in United States Patent No. 929,004, dated July 27, 1909. The resulting article of refractory material is a solid body through which the small fragments of liquefiable hydrocarbon are thoroughly distributed. The further step in this process is the complete impregnation of the body of composition prepared as above described with, a hydrocarbon which may or may not be solid at ordinary atmospheric temperature, thou h I believe it to be preferable to select a ydrocarbon such as gilsonite which is hard at ordinar temperatures and requires a considerab e use of tem erature in order to liquefg, it;

thoroug ly. Low melting point asp alts cannot be ground as they become gumm or sticky. Preferably, also, I thoroughly eat the sheet, slab or other article of refractory composition prepared as above described be- ,fore immersmg it in the hot liquefiable hydrocarbon which is to saturate it. This preliminary heating softens and may be carried to such temperature as to liquefy the included particles of hydrocarbon in the body; the heating also is effective to drive out a large pro ortion of the air inclosed in the pores o the composition. I then immerse the composition in a body of hot liquefied hydrocarbon which at once penetrates the porous refractory material. It is, I believe, also referable to employ for the impregnatin iiydrocarbon the same as, or a closely simifiir substance to, that which in comminuted form is distributed through and included in the body of the refractory material. I also recommend that the temperature of the impregnating hydrocarbon be maintained at a degree sufliciently hi h to insure the thorough liquefaction of t e included particles of the hydrocarbon in the refractory body.

The efiect of the presence in the body of a large number of hydrocarbon particles which are either softened or ii uefied by previous treatment or by the heating due to immersion in the path of hot liquid hydrocarbon, is to render the refractory composition extremely susceptible to and absorptive of the impregnating hydrocarbon liquid which penetrates to all portions of the refractory body with far greater celerity than in the case of a refractory body of similar nature but unprovided with included particles of hydrocarbon. I have observed some instances of the thorough impregnation of a refractory body of the character above described in one hour, whereas a similar body havin similar dimensions but unprovided with included hydrocarbons, has required 242 hours of immersion before complete saturation.

The preparation of comminuted hydrocarbon to-be added to the original mixture may vary considerably without sensibly affecting the final result. I have found in the case of gilsonite that about 10% by weight of gilsonite in the solid ingredients of the original mixture, sufiices to prepare the product for subsequent impregnation with a similar hydrocarbon under the conditions above described. 7

I What I claim and desire to secure by Letters Patent is:

1. The process which consists in first form ing a compacted composition of fibrous material, cement and finely divided liquefiable solid. hydrocarbon distributed therethrough,

and then immersing the said composition in liquefied hydrocarbon at a temperaturesuficiently high to liquefy the included hydrocarbon,

2, The process which. consists in first forming a compacted composition of asbestiform 1 fiber, a cement, and finely divided liquefiable solid hydrocarbon distributed there through and then immersing the said composition in 1i uefied hydrocarbon at a temperature sufiiciently high to liquefy the hydrocarbon included in the composition.

3. The process which consists in first forming a compacted composition of asbestiform fiber cemented with magnesium hydrate and containing finely divided liquefiable solid hydrocarbon distributed therethrough, and then immersing the said composition in a liquefied body of the same hydrocarbon.

i. The process which consists in first forming a compacted composition of fibrous macomposition in a liquefied hydrocarbon at a temperature sufiiciently high to' maintain the liquefaction of the included hydrocarbon.

5. The process which consists in first forming a compacted composition of asbestiform fiber, a cement, and finely divided liquefiable hydrocarbon distributed therethrough, then heating the composition to a temperature sufficiently high to liquefy the included hydrocarbon, and thereafter immersing the hot composition in liquefied hydrocarbon at a temperature suificiently high to maintain the liquefaction of the included hydrocarbon.

(i, The process which consists in first forming a composition of asbestiform fiber cemented with magnesium oxid, and containing finely divided .liquefiable solid hydrocarbon distributed therethrough, then heat-l mg the composition to a temperature Suficiently high to liquefy the included hydrocarbon, and thereafter immersing the hot composition in a liquefied body of the same hydrocarbon Signed by me at Boston, Massachusetts this tenth day of December 1909.,

7 WILLIAM R. SEIGL Witnesses:

Gnlrm s D, Woonnnaar, Josnrnrnn RYAN. 

